Tourist Visa
1. The clients can apply through the Iran embassy of their country. The Iran embassies will get the needed documents and will answer your request in the accurate duration. If the embassy refused your application OR want the invitation letter OR the authorization number OR the hotel voucher, you can apply through the second way. Mostly the visa issuance process would take longer. The entire visa issuance service fee will be paid to the embassy directly.
2. This is the most secure and easiest way to get the visa to Iran. Based on your nationality and the travel date, you will be guided while contacting first.
Required documents:
- Two completed visa application forms
- Valid passport, for at least 6 months
- 3 recent photos ( size 3×4 cm)
- Visa fee
- Return envelope with address and prepaid postage to cover cost of registered mail.
* – Interview, if necessary

more info: http://iran-visa.com/iran-visa-types/#Tourist-Visa

Airport entry Visa
It is recommended to those travelers who suddenly decide to travel to Iran and does not have any more time to apply through the travel agency. It is the Iran Airport Visa. It is valid for just 15 days and if the traveler wants to stay longer should extend it in Iran through the Iran interest foreign section. Just 64 nationalities can get the airport visa. Applicants holding ordinary passports may apply for a 15-day tourist/pilgrimage visa on arrival at the Passport and Visas Offices at Intentional Airports of Iran.
Airport Visa is granted at Imam Khomeini International Airport (IKIA), Kish, Shiraz, Tabriz, Mashhad, Isfahan and Chahbahar airports.
Required document:
- Visa application forms to be completed at Airport
- Valid Passport, for at beast 6 months.
- 2 recent photos ( size 3×4 cm)
- Visa fee
- Confirmed ticket to the third country for the applicants of 48 hour transit visa.
- Confirmed ticket for the applicants of 72 – hour visa, and a written request by the Iranian sponsor must be sent to the passport and Visa department- Ministry of Foreign Affairs at Airport branch.

more info: http://iran-visa.com/iran-visa-types/#Airport-entry-Visa

Transit Visa
Iran transit visa is suitable for those who like to pass from Europe to South Asia or who intend to travel to a third country through Iran’s territory. It is issued for limited time of 5, 7 or 10 days.
Required documents:
-Two completed visa application forms
- Valid passport for at least 6 months
- 3 recent photos (Size 3×4 cm)
- Valid visa for third country
- Confirmed air ticket for individuals who travel by air
- Visa fee
- Return envelope with adequate prepaid postage to cover cost of registered
* – interview if necessary.

more info: http://iran-visa.com/iran-visa-types/#Tranit-Visa

Safety: In general, Iran is much safer than Westerners might expect. Most people are genuinely friendly and interested to know about you and your country, so leave aside your preconceptions and come with an open mind. Iran is still a relatively low-crime country, although thefts and muggings have been on the increase in recent years.

Currency: Iranian Rial (IRR)

Language: Persian (called fārsi in Persian, فارسی), an Indo-European language, is Iran's national and official language.
Many young Iranians in major cities, and almost certainly those working in international travel agents and high-end hotels will speak conversational English but basic Persian phrases will definitely come in handy, particularly in rural areas.
Road signs are often double signed in English

Customs: Customs regulations related to tourists arriving Iran
Based on the regulations of developing tourism industry Act, tourists are allowed to bring the following goods. Provided that they wouldn't be commercial and at the time of departure they should possess the same goods.

List of the accompanied goods of tourists which should be registered by customs office

A) Personal jewelleries, one camera, one non professional video camera, one eye camera, one portable music instrument, one radio and portable music player and recorder, one portable personal computer, first aid box, one tent for camping and related tools, sport equipments such as equipments for fishing, skiing…. Etc

B) Export of one kilogram of caviar sealed by Shilat company and bought from Shilat market located at air port is allowed.

C) Tourists are allowed to bring out handicrafts or permitted products of the country in addition to their personal goods provided that they wouldn't be for commercial purposes.
Note:
Each tourist can bring all importable goods subject to customs exceptions related to other passengers.
more info: http://www.irica.gov.ir/Portal/Home/Default.aspx?CategoryID=83a7e5f0-4928-49c8-9ec3-53bd46cee05f